Short story: my Factory Windshield Wipers, Oil Pressure Gauge, Temp. Gauge, Fuel Gauge and Turn Indicators quit working when it was raining, so I thought it might be a short.
After checking my wiring and ignition switch, which are all in pretty good shape considering forrestbump's age, I stumbled on the possibility that the cause of failure for all these items simultaneously might be my "Instrument Panel Voltage Regulator" giving up the ghost. Found this out right here at FORDification from some old posts.
Just thought I'd pass this bit of information along to all others here that may be having the same issues and/or are as electrically challenged as I am.
Now I just need to get a new IPVR then install it.

Larry